One known type of door includes a substantially rectangular frame with opposing faces or skins attached to each side thereof. The resulting structure has a hollow interior space located between the two skins and bordered by the frame. Because the skins are often constructed from a relatively lightweight material, various fillers or support structures are often provided between the skins in the hollow interior space to provide increased structural integrity and to resist flexing of the skins if one were to push on them to open or close the door.
The door skins are sometimes flat sheets of material with a substantially planar outer surface. In other instances, the skins may be provided with decorative features, such as, for example, indentations that produce areas on the surface of the door that are raised or lowered with respect to adjacent areas on the door. In certain doors, for example, the skins will have one or more areas that are recessed inwardly toward the hollow space between the skins. It is often the case that both skins have the same recessed pattern. In such instances, the distance between the interior faces of the skins in the hollow space varies across the surface of the skins. For example, the distance between the skins in the recessed areas will be less than the distance between the skins in the non-recessed areas.
One embodiment of the present invention includes a method of installing a reinforcing structure in a door. The door has first and second stiles, first and second rails and first and second skins. The first skin has a first surface, a second surface and a recessed area defined by a perimeter. The recessed area of the first skin has a first surface that is recessed with respect to the first surface of the first skin and a second surface that extends beyond the second surface of the first skin. The second skin has a first surface, a second surface and a recessed area defined by a perimeter. The recessed area of the second skin has a first surface that is recessed with respect to the first surface of the second skin and a second surface that extends beyond the second surface of the second skin. The method includes the steps of securing the second surface of the first skin to the first and second stiles and the first and second rails, providing a reinforcing structure having a first region, a second region and a third region, securing the reinforcing structure to the second surface of the recessed area of the first skin and securing the second surface of the second skin to the first and second stiles and the first and second rails.
In one embodiment of the invention, the reinforcing structure is secured entirely within the perimeter of the recessed area of the first skin.
In another embodiment, at least one region of the reinforcing structure is an expandable corrugated paperboard structure. In another embodiment, the first and third regions of the reinforcing structure are non-expandable corrugated paperboard structures. The second region may be located between the first and third regions of the reinforcing structure.
In certain embodiments of the invention, the reinforcing structure is constructed from a single grade of corrugated paperboard. In other embodiments, the reinforcing structure is constructed from multiple grades of corrugated paperboard. In one embodiment, the first region of the reinforcing structure is constructed from a first grade of corrugated paperboard and the second and third regions of the reinforcing structure are constructed from a second grade of corrugated paperboard.
In other embodiments of the present invention, at least one region of the reinforcing structure is an expandable corrugated paperboard structure and the method further includes the step of expanding the expandable corrugated paperboard structure in the direction of the stiles prior to securing the reinforcing structure to the second surface of the recessed area of the first skin.
In another embodiment of the present invention, the method includes the step of providing a second reinforcing structure and securing it to the second surface of the first skin and the second surface of the second skin.
In one embodiment of the present invention, a reinforcing structure for a door includes a first region constructed from a first grade of corrugated paperboard and second and third regions constructed from a second grade of corrugated paperboard. The first region may be expandable and the second and third regions may be non-expandable.